Long Term Evolution (LTE for short) is long term evolution of a universal mobile telecommunications system (Universal Mobile Telecommunications System, UMTS for short) technological standard formulated by the 3rd Generation Partnership Project (3rd Generation Partnership Project, 3GPP for short).
According to different duplex modes, LTE is classified into two types: frequency division duplex (Frequency Division Duplex, FDD for short) and time division duplex (Time Division Duplex, TDD for short). In the FDD mode, uplink and downlink link channels use different frequencies, and a frame of a fixed time length is used during both uplink and downlink transmission. In the TDD mode, uplink and downlink links share a same frequency, and transmission is performed in different timeslots.
According to different carrier combination manners used by a terminal, carrier aggregation (Carrier Aggregation, CA for short) is classified into three types: intra-band continuous CA, intra-band non-continuous CA, and inter-frequency band CA. Frequency resources in global markets are different from each other, and different types of CA have respective application scenarios. The three different types of CA are included in both the FDD mode and the TDD mode. Therefore, a total of six types of CA in the FDD mode and the TDD mode need to be implemented by using different radio frequency front-end hardware architectures.
According to a demand of an actual application scenario, it is required that a terminal support a total of six CA technologies. However, an existing terminal cannot very well support a total of six or even more CA technologies that may be combined, and therefore design of the existing terminal is insufficiently flexible.